Impact actuator for rockable print wheels



Dec. 12, 1967 H. cs. HARRISON 3,357,348

IMPACT ACTUATOR FOR ROCZZABLE PRINT WHEELS 6 Sheets-Sheet 1 Filed May 21 1965 INVENTOR:

HERBEfiTG. HARRISON BY o a mm ATTORNEYS Dec. 12, 1967 H. G. HARRISON 3,357,348

IMPACT ACTUATOR FOR ROCKABLE PRINT WHEELS Filed May 21 1965 6 Sheets-Sheet 2 Inventor H ERT 6. #A-RRLSDN By g M A ltorney5 Dec. 12, 1967 H. e. HARRISON 3,

IMPACT ACTUATOR FOR ROCKABLE PRINT WHEELS 6 Sheets-Sheet 5 Filed May 21 1965 Inventor b emer 6. #4122160 By Mia A tlorneys Dec. 12, 1967 H. G. HARRISON 3,357,348

IMPACT ACTUATOR FOR ROCKABLE PRINT WHEELS 6 Shets-Sheet 4 Filed May 21 1965 .WDQ \%W M t H \u V e r v H I w k 6% m I MSW www \QW l l I I .l I. m, E

f wserer 6. link/501v By Mia & M12,

A Home y5 Dec. 12, 1967 H. G. HARRISON 3,357,348

IMPACT ACTUATOR FOR ROCKABLE PRINT WHEELS Filed May 21 1965 6 Sheets-Sheet 5 Inventor H 'KBE'ET 6. AARRLSOAI By t & Mt

Attorneys Filed May 21 1965 Dec. 12, 1967 so 3,357,348

IMPACT ACTUATOR FOR ROCKABLE PRINT WHEELS 6 Sheets-Sheet 6 [nvenlor Mensa-2r G. llfiPlO/V A Horneys United States Patent 3,357,348 IMPACT ACTUATOR FOR ROCKABLE PRINT WHEELS Herbert G. Harrison, Enfield, England, assignor to English Numbering Machines Limited, Enfield, England, a British company Filed May 21, 1965, Ser. No. 457,680 Claims priority, application Great Britain, May 25, 1964, 21,463/64 7 Claims. (Cl. 10194) The present invention relates to printing devices.

It isan object of the present invention to provide a printing device which enables one or more printing elements to exert a predetermined printing impact pressure.

Another object of the invention is to provide a printing device comprising spring means which during a first phase of each operation are tensioned always to the same degree, independently of the setting of type wheels and of the speed at which an operating member is actuated, these spring means being disconnected during a second phase of operation during which printing is effected.

The invention resides in a printing device performing a three phase cycle of operation for each print, the device incorporating the combination of features which will hereinafter be described and claimed in the appended claims.

Further objects and advantages of the invention will be more readily understood by those skilled in the art from the following description thereof which is given by way of example, with reference to the accompanying drawings, wherein:

FIG. 1 is a general perspective, somewhat diagrammatical view of a first printing device of the invention;

FIG. 2 is a side view of the mechanism of the printing device of FIG. 1;

FIG. 3 is a perspective view showing parts of the mechanism shown in FIG. 2;

FIG. 4 is similar to FIG. 2, but shows the mechanism in its printing position;

FIGS. 5 and 6 illustrate a detail of the mechanism of.

FIG. 2 in different operating positions;

FIG. 7 is a side view partly in section and partly broken away of a second printing device and its mechanism;

FIG. 8 is a side view similar to FIG. 7, but with parts of the second printing mechanism in different positions; and

FIG. 9 shows in side view parts of the second printing mechanism.

The printing device of FIG. 1 comprises a casing generally indicated by reference numeral 500. The casing houses a printing mechanism parts of which are indicated in broken lines. The casing 500 comprises a first wall 501, a rear wall 502, side walls 503 and 504, a bottom wall 505, and a top wall 506. The side wall 504 has a slot 507 through which a lever 1 of the printing mechanism extends for operating the mechanism. The top wall 506 has a slot 508 through which a handle 22 of the printing mechanism extends for indexing a printing Wheel of the printing mechanism. Through an opening 511, a counter surface 19 for co-operation with the printing wheel is accessible. The counter surface 19 is provided on a sheet 191 of synthetic plastic material mounted on a rigid block 192 carried by the front and rear walls 501 and 502.

The operating lever 1 of the printing mechanism (see also FIGS. 2 and 3) is pivotally cam'ed on a shaft 101 fixed to the front and rear walls 501 and 502 of the easing 500 and has a free end arranged to co-operate with a cam 2 and connected to one end of a spring 12. The cam 2 is adjustably secured to a support bar 3a secured between shafts 4 and 4a. The shaft 4 is fixed to the front and rear walls 501 and 502. The shaft 4a is mounted-between a pair of tripping members in the form of levers 3 at opposite ends of the shaft 4a, and the levers 3 are pivo'table, with the support bar 3a, the earn 2 and the shaft 4a about the shaft 4. A spring 103 connected to the shaft 4:: and a stub shaft 104 fixed to the rear wall 502 (see FIGS. 1 and 3) tends to rotate the lever 3 in clockwise direction as viewed in FIG. 3.

The free ends of the levers 3' are notched for engagement with a shaft 42' and form a first tripping device. The shaft 42 is secured at opposite ends in a pair of lever elements 5. The shaft 42 and the lever elements 5 are locked by a second tripping device 8 to a haft 43, and thus to a pair of lever elements ,6 connected to opposite ends ofthe shaft 43'. The second tripping device 8'is rotatable about the shaft 42 and has a recess engaging the shaft 43 when the mechanism is in the position shown in FIGS. 2 and 3, the shaft 43' being disengaged from said recess when the second tripping device 8 is rotated in counterclockwise direction as viewed in FIGS. 2 and 3 against the action of a spring (not shown). The lever elements 5 and 6 are rotatable about a shaft 7 which is secured in the front and rear walls 501 and 502 of the device. A spring 12 is secured to a shaft mounted at opposite ends in the lever elements 6, and, when stressed tends to rotate the lever elements 5' and 6, when locked together by the tripping device 8, in the direction .of arrow B. A shaft 14 secured tothe lever elements 5 engages in .a slot 17 (see also FIGS. 5 and 6) in a pivotally mounted support 15, which is pivotable about a shaft 16 mounted in the front and rear walls 501 and 502 of the device, and the support 15 carries a printing wheel 18 which, on rotation of the support 15 in the direction of arrow C, co-operates with the counter surface 19.

A second spring 13, which is weaker than the spring 12 and is secured at one of'it's ends to a shaft extending between and fixed to armsSl of the lever elements 5 and at its otherend to a shaft 11' fixed in the front and rear walls 501 and 502, tends to rotate the lever elements 5 in the direction opposite to the direction indicated by the arrow B.

An abutment in the form of a pin 10 is arranged to co-operate with a projection 81' on the second tripping device 8 for rotating the latter about the shaft 42'during rotation of the lever elements 5 about the shaft 7 in the direction of arrow B.

The printing wheel 18 has a plurality of printing faces 181 and meshe 'with an intermediate toothed wheel 24 which in turn meshes with a toothed setting member in the form of a toothed segment 23 provided with the handle 22 and rotatable with friction about the shaft 101. A pawl 26 engages between the teeth of the intermediate toothed'wheel 24 under the actionof a spring 25.

1 The operation of the mechanism described is as folows:

A sheet of paper, cardboard or the like to be printed is placed on the counter surface 19 and a suitable inking device, for example a carbon paper (not shown), is provided. The printing wheel' 18 is indexed ,by rotating the toothed segment 23 by means of the handle 22, this rotation being imparted to the-printing wheel 18 through the intermediate toothed wheel 24. The lever 1 is then pivoted about the shaft- 101- in the direction indicated by arrows A1, A2, whereupon the free end of the'lever 1 tensions the spring 12 and eventually'strikesthe cam 21 When the lever-'1 strikes the cam 2, the tripping levers 3 forming the first tripping device are rotated about the shaft 4' so that their notched ends 41 move out of engagement with the shaft 42, which is locked by means of the second tripping-device S-tO the lever element 6. When the tripping levers 3 forming the first tripping device have been moved out of engagement with theshaft' 42, the lever elements 5 and 6 :are no longer connected through the'levers 3 to-the stationary shaft- .4 and, thus, are now free to rotate together about the shaft 7 under the action of the spring 12 in the direction of the arrow B, so that the pin 14 in the slot 17 moves upwards as viewed in FIG. 2 and causes the support 15 to rotate about the shaft 16 in the direction of the arrow C to effect a print in co-operation with the counter surface 19.

As the lever elements 6 rotate as described in the direction of the arrow B during a firstphase of operation, the weak spring 13 is tensioned. Owing to the rotation of the levers in the direction of the arrow B, the projection 81 of the second tripping device 8 strikes the abutment pin 10. Thereby, the second tripping device 8 is rotated about the shaft 42 and releases the shaft 43, so that the lever elements 6 are no longer locked to the lever elements 5. During a second phase of operation after the release of the shaft 43 and owing to the momentum of the support 15 provided by the spring 12 the printing wheel 18 continues to move in the direction of the arrow C until it strikes the paper, cardboard or the like to be printed on the counter surface 19 (see FIG. 4) and effects a print, whereupon the lever elements 5 and therewith the support 15 reverse their direction of movement about the shaft 7 under the action of the spring 13 until the lever elements 5 and the support 15 have returned to their initial position shown in FIG. 2. When this position has been reached and, at any time after actuation, the operating lever 1 has been returned to its initial position the spring 12 contracts and pushes hke a rigid rod the lever elements 6 into their initial position; furthermore, the spring 103 turns the levers 3 to re-engage the shaft 42 and the second tripping device 8 under spring action reengages the shaft 43, so that the mechanism is ready for a next cycle of operations.

While the support 15 is displaced from its initial position, the pawl 26 engaging the intermediate toothed wheel 24 ensures that the printing wheel 18 does not rotate. Friction prevents the toothed segment 23 from rotation so that re-engagement of the same teeth of the toothed segment 23 and of the intermediate toothed wheel 24 is ensured on return of the support 15 into its initial position. However, the shape of the pawl 26 is such that it does not prevent the intermediate toothed wheel 24 from being readily rotated by the toothed segment 23 when the support 15 is in its initial position.

FIG. 5 shows on a larger scale the pin 14 in the slot 17 of the printing wheel support 15. FIG. 6 shows the pin 14 and the slot 17 in a different relative position. As can be seen from FIG. 6, the support 15. is slotted at 151 to allow for some flexibility to compensate for manufacturing tolerances.

From the foregoing description it will be seen that a complete cycle of operations consists substantially of three distinct phases: When the operating lever 1 has been actuated in a first phase of the operation, the spring 12 is tensioned always to the same degree and the first tripping device formed by the levers 3 is operated to release the shaft 42 whereupon the lever elements 5 and 6 rotate jointly until the second tripping device 8 releases the shaft 43 at the beginning of the second phase, during which the lever elements 5 continue to rotate, but now rotate independently of the lever elements 6, until a print iseifected when the mechanism has reached the position of FIG. 4 whereupon during a third phase, under the action of the spring 13 the mechanism returns to its initial position of FIGS. 2 and 3. Owing to the fact that the spring 12 always is tensioned to the same degree, the same printing impact by the printing wheel 18 on a surface 6 to be printed is obtained so that, if other conditions remain the same, uniform prints can be obtained during successive cycles of operations, independently of whether the operating lever 1 is actuated quickly or slowly or when after having been actuated the lever 1 is returned to its initial position.

The printing mechanism illustrated in FIG. 7 is housed in a casing generally indicated by reference numeral 600. The casing 600 comprises a front wall 601, a rear wall 602, side walls 603 and 604, a bottom wall 605 anda top wall 606. The various shafts of the mechanism are fixed to the front and rear walls 603 and 604 of the casing 600. The printing mechanism has a lever 201 corresponding to the lever 1 of FIG. 2 for actuating the mechanism. A coil spring 202 is secured at one end to the lever 1 and at its opposite end to a lever element 203.

A pin 205 on the lever 201 is arranged to cooperate with a cam surface 206 on a first tripping device in the form of a tripping lever 207 which is pivotable about a shaft 209 and which at its end opposite to the cam surface 206 is formed with a notch 211 engageable with a pin 212 on a lever element 213.

The lever elements 203 and 213 are pivotable about a shaft 214. A second tripping device in the form of a tripping member 206 is pivotally secured to the lever element 213 and formed with a notch 207 engaging a pin 208 on the lever element 203 when in the position shown 1nv FIG. 7. The tripping member 206 thus serves to lock the lever elements 213 and 203 together. The tripping member 206 may conveniently be of sheet metal which is bent to form a projecting ledge 215, which, upon rotation of the lever element 213 about the shaft 214 in the direction of arrow D as described below, contacts an adjustable abutment 216.

A lever 220 is pivotally connectedat one end to the pin 212 and at its other end to a pin 219 which is slidable in a slot 221 in a support part 222. A lever 224 is pivotally connected at one end to the pin 219 and at its other end to a shaft 215, and the support part 222 and a support plate 226 are pivotable about a shaft 218.

A printing wheel 230 formed with a plurality of teeth 231 each having a printing surface 232 is rotatably carried on thesupport plate 226. The teeth 231 of the printing wheel 230 mesh with teeth 234 of a setting wheel 235 which is rotatable about the shaft 214 for indexing the printing wheel 230.

The setting wheel 235 has a tooth 237 which is larger than the teeth 234 and which is shaped to co-operate with a notch 238 formed in a locking member 239 pivotally secured to the support plate 226 by a pivot pin 301. The locking member 239 is formed with a further notch 241 for engagementwith the shaft 215 the locking member 239 also having a projection 242 shaped for engagement in a notch 243 in the support part 222 for securing the latter to the support plate 226. A nose 245 on the locking member 239 co-operates with a spring 246, which serves to maintain the locking member 239 in engagement with either the shaft 215, in which case the support plate 226 is locked in the initial position shown in FIG. 7 while the support part 222 is free to move relative to the support plate 226, or in engagement with the support part 222, in which case the support part 222 and the support plate 226 are locked together and the suPP plate 226 is able to pivot from its initial position about the shaft 218 as will be described below.

A pawl 250 urged into contact with the printing wheel 230 by a spring 251 is formed with a projection 252 which cooperates with a corresponding projection 253 at one end'. of a pawl 254 to maintain the pawl 254 in engagement with the teeth 234 of the setting wheel 235 when the support plate 226 is in its initial position. The other end of the pawl 254 is formed with an arcuate projection 256 which: co-operates with a pin 257 on the lever 201 so that when the lever 201 is rotated in the direction of the arrow D from the position shown in FIG. 7 the pin 257 contactsthe projection 256 and thus maintains the pawl 254 in engagement with the teeth 234 when the projection 252 moves out of contact with the projection 253.

The lever element 213 is secured at its free end 258 to one end of a coil spring 259, which is weaker than the spring 202 and which is secured at its other end to a shaft 260.

The operation of this printing device is as follows:

By rotation of the setting wheel 235, the printing Wheel 230 is indexed into its desired position for printing, whereby the tooth 237 is rotated in the direction of the arrow D from the position shown in FIG. 7 so as to move the projection 242 on the locking member 239 into engagement with the notch 243 in the support part 222 as shown in FIG. 9.

The lever 201 is then pivoted in the direction of the arrow D about the shaft 214, while the lever elements 203 and 213 are locked in position by the tripping lever 207 and are locked together by the tripping member 296, so that the spring 202 is tensioned. The pivotation of the lever 201 brings the pins 205 into contact with the cam surface 2061 and causes the tripping lever 207 to rotate against the action of a spring 261 about the shaft 209 to disengage the notch 211 from the pin 212. The lever elements 203 and 213, still locked together by the tripping member 206, are during a first phase of operation pivoted by the action of the spring 202 in the direction of arrow D about the shaft 214. Through the lever 218, this pivotation raises the pin 219 and thus causes the support part 222 and the support plate 226, which are locked together by the locking member 239, to pivot about the shaft 220 from the initial position shown in FIG. 7 in the direction of the arrow E.

Upon further pivotation of the lever elements 203 and 213 in the direction of the arrow D, the ledge 215 strikes the abutment 216 which at the beginning of a second phase of operation causes the tripping member 206 to rotate about the pin 212 and to disengage the pin 208. When this happens, the support part 222 and the support plate 226, with the printing wheel 230, continue to pivot under their own momentum provided by the spring 202 in the direction of the arrow B and against the action of the weaker spring 259 until the printing wheel 230 strikes a surface to be printed, the mechanism being then in the position shown in FIG. 8.

After a printing has taken place, the spring 259 during a third phase of operation, rotates the lever element 213 about the shaft 214 in a direction opposite to that indicated by the arrow D, so that upon return of the lever 201 into its initial position the printing wheel 230 is brought back into engagement with the setting wheel 235, the notch 211 is re-engaged by the pin 212 under the action of the spring 261 acting on the tripping lever 207, the lever element 203 is returned to its initial position by the closure of the coils of the spring 202, and the tripping member 206 is rotated about the pin 212 by a spring 263 into engagement once again with the pin 208. The printing device is then ready for a further cycle of operation.

It should be clearly understood that the embodiments described are given by way of example and that many modifications, omissions and additions are possible without departing from the scope and spirit of the invention.

I claim:

1. In a printing device of the kind comprising a printing wheel, a plurality of printing faces on said printing wheel, and means for setting said printing wheel to obtain a print from a selected one of said printing faces, the improvement comprising: an operating lever, a first lever element, a second lever element, means operatively connecting said printing wheel to said first lever element to effect a print on rotation of said first lever element, first spring means arranged for acting on said second lever element, and for being tensioned by said operating lever, first means for releasably locking said first lever element in position, second means for releasably locking said first lever element to said second lever element, second spring means weaker than said first spring means and arranged for acting on said first lever element in a sense opposed to the action of said first spring means, said second spring means being tensionable by said first lever element when moving under the action of said first spring means, first means for releasing said first locking means for permitting rotation of said first and second lever elements during a first phase of operation, said first releasing means being operable by said operating lever after it has tensioned said first spring means, and second means for releasing said second locking means for permitting independent movement of said first and second lever elements during a second phase of operation, said second spring means during a third phase of operation returning said first lever element.

2. In a printing device of the kind comprising a printing wheel, a plurality of printing faces on said printing wheel, and means for setting said printing wheel to obtain a print from a selected one of said printing faces, the improvement comprising: an operating lever, a first lever element, a first tripping device for locking said first lever element in position, means operatively connecting said printing wheel to said first lever element to effect a print on rotation of said first lever element, a second lever element, a second tripping device on one of said lever elements and arranged for locking said second lever element to said first lever element for joint rotation, first spring means connected between said operating lever and said second lever element, said first spring means being arranged to be tensioned by said operating lever when actuated, a first abutment on said first tripping device, said first abutment being arranged in the path of said operating lever for being struck by said operating lever when actuated and after tensioning said first spring means, said first abutment when struck tripping said first tripping device to release said first lever element for joint rotation with said second lever element under the action of said first spring means during a first phase of operation, a second abutment arranged in the path of said second tripping device to strike the same and thereby to trip said second tripping device to release said first and second lever elements from each other and thereby to allow independent movements thereof during a second phase of operation, and second spring means weaker than said first spring means and acting on said first lever element for returning the same during a third phase of operation into its initial position after a print has been effected.

3. A device as defined in claim 2, wherein said operatively connecting means comprise a support carrying said printing wheel, said support being rotatably mounted and being rotatable by said first lever element.

4. A device as defined in claim 2, wherein said first tripping device comprises a rotatably mounted lever carrying said first abutment which is arranged to be struck by said operating lever.

5. A device as defined in claim 2, wherein said first tripping device comprises a rotatably mounted lever carrying said first abutment, said operating lever carrying a pin at one end thereof, said first abutment being arranged to be struck by said pin.

6. A device as defined in claim 2, wherein said first and second lever elements are rotatable about a common axis, said operating lever being rotatable about an axis different from said common axis.

7. A device as defined in claim 2, wherein said operating lever, said first lever element and said second lever element are rotatable about a common axis.

References Cited UNITED STATES PATENTS 1,916,538 7/1933 Smith 101-95 2,281,851 5/1944 Mehan 10l96 2,346,265 4/ 1944 Mehan 101-96 2,492,263 12/1949 Boyden 10196 2,623,455 12/1952 Coutfignal 10196 2,800,074 7/1957 Busch et al 101-96 2,894,449 7/1959 Boyden et al. 101- 96 2,973,708 3/1961 Becker 101-95 WILLIAM B. PENN, Primary Examiner. 

1. IN A PRINTING DEVICE OF THE KIND COMPRISING A PRINTING WHEEL, A PLURALITY OF PRINTING FACES ON SAID PRINTING WHEEL, AND MEANS FOR SETTING SAID PRINTING WHEEL TO OBTAIN A PRINT FROM A SELECTED ONE OF SAID PRINTING FACES, THE IMPROVEMENT COMPRISING: AN OPERATING LEVER, A FIRST LEVER ELEMENT, A SECOND LEVER ELEMENT, MEANS OPERATIVELY CONNECTING SAID PRINTING WHEEL TO SAID FIRST LEVER ELEMENT TO EFFECT A PRINT ON ROTATION OF SAID FIRST LEVER ELEMENT, FIRST SPRING MEANS ARRANGED FOR ACTING ON SAID SECOND LEVER ELEMENT, AND FOR BEING TENSIONED BY SAID OPERATING LEVER, FIRST MEANS FOR RELEASABLY LOCKING SAID FIRST LEVER ELEMENT IN POSITION, SECOND MEANS FOR RELEASABLY LOCKING SAID FIRST LEVER ELEMENT TO SAID SECOND LEVER ELEMENT, SECOND SPRING MEANS WEAKER THAN SAID FIRST SPRING MEANS AND ARRANGED FOR ACTING ON SAID FIRST LEVER ELEMENT IN A SENSE OPPOSED TO THE ACTION OF SAID FIRST SPRING MEANS, SAID SECOND SPRING MEANS BEING TENSIONBLE BY SAID FIRST LEVER ELEMENT WHEN MOVING UNDER THE ACTION OF SAID FIRST SPRING MEANS, FIRST MEANS FOR RELEASING SAID FIRST LOCKING MEANS 